Catheter ablation of atrial fibrillation in patients with left ventricular dysfunction

There is a complex interplay between atrial fibrillation and congestive heart failure. These two clinical entities often coexist, resulting in significant morbidity, affecting prognosis and rendering their management even more challenging. New nonpharmacologic therapies are emerging and may alter the management of these patients. Among them, catheter ablation of atrial fibrillation seems to be a promising therapeutic approach as it leads to improvement of cardiac function, symptoms, exercise capacity, and quality of life. This article reviews the role of catheter ablation in contemporary management of atrial fibrillation among patients with left ventricular dysfunction

Severe accordion effect: Myocardial ischemia due to wire complication during percutaneous coronary intervention: A case report

A mechanical alteration during manoeuvring of stiff guidewires in tortuous coronary arteries frequently induces vessel wall shortening and coronary psedostenosis, referred as accordion phenomenon. Subtraction of the guidewires normally leads to the entire resolution of the lesions. A case of this transient angiographic finding, during percutaneous coronary intervention in a tortuous right coronary artery, which resulted in a flow limiting effect and myocardial ischemia, is described in the present report. Differential diagnosis from potential procedure complications and interventional methodology issues are discussed, while similar reports are reviewed

Torsade de Pointes related to the co-administration of amiodarone and digoxin

A case of acquired long QT syndrome and subsequent torsade de pointes related to the co-administration of amiodarone and digoxin is described in the present case report. The underlying electrophysiologic mechanism of this proarrhythmic event is discussed

The MIDAS dosimeter/particle monitor of charged particles and neutrons for space environment

Radiation doses received by astronauts outside the geomagnetic field are a main risk factor for human space exploration. The Miniaturized Detector for Application in Space (MIDAS) device is a highly miniaturized radiation detector (mass <50 g, volume < 5 × 5 × 1 cm3) which is under development using fully depleted monolithic active pixel sensors and a plastic scintillator readout by a Silicon Photomultiplier. Its purpose is to measure dose and dose equivalent from both charged particles and fast neutrons. The device simulated response to galactic cosmic rays spectra has been treated with artificial intelligence techniques i.e. multi-classification for particle identification and regression for the determination of the kinetic energy of protons. Results indicate that particle identification and kinetic energy determination with the aid of these methods could be a viable approach. © 2020 Elsevier Lt

Predictors of atrial fibrillation recurrence in patients with long-lasting atrial fibrillation

BACKGROUND: Limited data are available on the predictors of atrial fibrillation (AF) recurrence in patients with chronic AF.OBJECTIVES: To evaluate potential clinical, echocardiographic and electrophysiological predictors of AF recurrence after internal cardioversion for long-lasting AF.METHODS: A total of 99 consecutive patients (63 men and 36 women, mean age 63.33 +/- 9.27 years) with long-standing AF (52.42 +/- 72.02 months) underwent internal cardioversion with a catheter that consisted of two defibrillating coils. Shocks were delivered according to a step-up protocol. Clinical follow-up and electrocardiographic recordings were performed on a monthly basis for a 12-month period or whenever patients experienced symptoms suggestive of recurrent AF.RESULTS: Ninety-three patients (93.94 %) underwent a successful uncomplicated cardioversion, with a mean atrial defibrillation threshold of 10.69 +/- 6.76 J. Immediate reinitiation of AF was observed in 15 patients (15.78 %) of whom a repeated cardioversion restored sinus rhythm in 13 cases. Early recurrence of AF (within one week) was observed in 12 of 93 patients (12.90 %). At the end of the 12-month follow-up period, during which seven patients were lost, 42 of the 86 remaining patients (48.84 %) were still in sinus rhythm. Multivariate regression analysis showed that left atrial diameter (OR 1.126, 95 % CI 1.015 to 1.249; P=0.025) and mitral A wave velocity (OR 0.972, 95 % CI 0.945 to 0.999; P=0.044) were significant and independent predictors of AF recurrence, whereas age, left ventricular ejection fraction and AF cycle length were not predictive of arrhythmia recurrence.CONCLUSION: The present study showed that the left atrial diameter and mitral A wave velocity are the only variables associated with AF recurrence after successful cardioversion

MIDAS: A Miniature Device for Real-Time Determination of the Identity and Energy of Particles in Space

The Miniaturized Detector for Application in Space (MIDAS) device is developed in response to the requirement of the European Space Agency for a device whose size, power consumption, and radiation data output would increase the level of space-flight crew autonomy regarding operational decisions related to radiation hazards. It is designed as a wristwatch-dimension cube detector for measuring track direction and energy deposition in silicon pixels, as well as energy depositions by neutrons in a plastic scintillator, which is the core of the cube. Miniaturization was achieved by using fully depleted silicon pixel detectors with the signal processing electronics residing on pixel. The device concept, simulated performance, and first measurements are presented. Simulation results indicate that it is possible to discriminate all significant ions with the aid of appropriate variables constructed using the data provided by the device. 252Cf energy spectra were reconstructed successfully using measurements obtained with the first device prototype. © 2020. The Authors